More and more democratically elected world leaders have openly sought to fuel a climate of hatred toward the media over the last 12 months, according to a study.

The latest annual world press freedom index, compiled by Reporters Without Borders (RSF), found a growing sense of "hostility" toward the media was "no longer limited to authoritarian countries."

The index, published Wednesday, highlighted a "slow erosion" of press freedom in Europe and an increasing amount of unprecedented attacks on journalists in democratically elected governments.

"The unleashing of hatred towards journalists is one of the worst threats to democracies," RSF Secretary-General Christophe Deloire said.

"Political leaders who fuel loathing for reporters bear heavy responsibility because they undermine the concept of public debate based on facts instead of propaganda. To dispute the legitimacy of journalism today is to play with extremely dangerous political fire," he added.

'Fake news'

North Korea, Eritrea, Turkmenistan, Syria and China all languished at the bottom of the 180 countries ranked by the RSF in 2018. Norway and Sweden topped the index for the second-straight year.

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A view of the Oslo business district at dusk. Norway topped the rankings for the second year running in the RSF's 2018 world press freedom index.

The U.S. slipped two places to rank 45th out of the 180 countries. Its decline was due, in part, to President Donald Trump's frequent castigation of journalists. He was described as a "media-bashing enthusiast" by the RSF in its latest report.

In February 2017, Trump said the U.S. media was "the enemy of the American people." He has also referred to the U.S. media as the "opposition party" and has regularly blamed news outlets for stymieing his political agenda.

"The U.S.' decline in press freedom is not simply bad news for journalists working inside the country; the downward trend has drastic consequences at the international level. 'Fake news' is now a trademark excuse for media repression, in both democratic and authoritarian regimes," the RSF said.

China's 'oppressive' influence

The RSF also found Europe, which is the region seen to have the most respect for press freedom, sustained four of this year's five biggest falls in the index. The report singled out journalists who were subject to physical attacks and death threats in Malta, Italy and Poland and also highlighted the use of anti-media rhetoric from lawmakers in the Czech Republic, Hungary and Slovakia.

Meanwhile, in Asia, the influence of China's "oppressive methods, information censorship system and internet surveillance tools" could be seen in a number of other countries in the region. Vietnam, Cambodia, Thailand, Malaysia and Singapore were all cited as states "struggling to defend their models against an all-powerful China."

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Chinese President Xi Jinping.

One notable exception was Taiwan, the RSF said. It topped the rankings for the continent.

The index — which has been published annually since 2002 — evaluates countries around the world by the "level of pluralism, media independence, the environment and self-censorship, the legal framework, transparency, and the quality of infrastructure that supports the production of news and information."